/*
 * Copyright (C) 2011 David
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.sherlock.downloader.fetchers;

import java.io.RandomAccessFile;

import org.sherlock.commons.download.FetcherException;
import org.sherlock.commons.download.FetcherProxy;
import org.sherlock.downloader.Download;
import org.sherlock.downloader.Download.Status;

/**
 *
 * @author David
 */
public abstract class Fetcher implements Runnable, FetcherProxy {

    protected Download download;
    protected RandomAccessFile file;

    public Fetcher(Download download) {
        this.download = download;
    }

    public void cancel() {
        download.setStatus(Status.CANCELLED);
    }

    public void download() {
    	download.setStatus(Status.DOWNLOADING);
    }

    public void pause() {
        download.setStatus(Status.PAUSED);
    }

    public void resume() {
        if (download.getStatus() != Status.DOWNLOADING) {
            download();
        }
    }

    public abstract void connect() throws FetcherException;

    public void initialize() throws FetcherException {
        try {
            initializeFile();

            download.setFetcher(this);
            connect();
            download.setStatus(Status.READY);
        } catch (Exception ex) {
            ex.printStackTrace();
            throw new FetcherException();
        }
    }

    private void initializeFile() throws Exception {
        int downloaded;
        file = new RandomAccessFile(download.getLocalURL().getPath(), "rw");
        downloaded = (int) file.length();
        file.seek(downloaded);
        download.setDownloaded(downloaded);
    }
}

